What I want
I want to upgrade 'cause my CPU starting to grow old and weak in new game.

I want a good upgrade (shouldn't be hard) for my CPU (and by extension my motherboard and RAM).
I don't really know what to look for, there is so much motherboard and CPU.

I might want to overclock.

I will also need a new case
Coolermaster Elite 370 34.65$
Silverstone Precision PS04B 36.43$
Silverstone Precision Series PS05-B 39.99$
Thermaltake V4 39.10$
Antec Two Hundred 45.99$
Antec Three Hundred 49.79$
Some other if you want.

I need a case with good air cooling, I already have 2 antec 120mm tri-cool in my current case.
I also want enough place to enter card size like the 6870 (or near it).
I also want place to enter a good CPU cooling like a Hyper 212+ or a Noctua NH-U12P SE2 (in the future).

I don't know what I should get, intel, amd, or wait for the new amd platform.

I might also want to ADD PSU+HDD+Keyboard+mouse to keep my old computer and put in the living room. If it happen I would put something near 500$.

I'm going to buy from ncix.com

I'm probably going to buy it in january/after christmas.

Thank you for your help.

Almost forgot1. What YOUR PC will be used for. That means what types of tasks you'll be performing.
Gaming, video encoding.2. What YOUR budget is. A price range is acceptable as long as it's not more than a 20% spread
sub 400$MAX before taxe and shipping3. What country YOU will be buying YOUR parts from.
Canada4. IF YOU have a brand preference. That means, are you an Intel-Fanboy, AMD-Fanboy, ATI-Fanboy, nVidia-Fanboy, Seagate-Fanboy, WD-Fanboy, etc, etc, etc, you get the picture.
AMD and ATI fanboy, but I really don't care about having something else5. If YOU intend on using any of YOUR current parts, and if so, what those parts are.
GPU (4850 512mb), PSU (TP3-550 watts antec), HDD (look at my spec), DVD drive.7. IF YOU plan on overclocking or run the system at default speeds.
Some overclock.8. WHEN do you plan to build it?
after christmas/ start January.9. What resolution do you use?
1680*1050

But a quad 940 won't support anything else than DDR2, wouldn't it be a waste when I will want to upgrade again. Since DDR3 cost almost nothing now.

I read the topic on the PS04B on this forum, it look good but i'm not sure if the air cooling is enough, 1 front and 1 rear is not that much. Wouldn't something like the antec 300 would have more cooling potential?

sb driving prices down... could you define sb please, never heard this term before.

I don't really want to think about a i3, It's a dual core I think a quad core might offer me best performance for a longer time in game (future game).
Of course, the i3 at 4ghz seem bloody interesting,

Here is what I have
All build have
CMV4GXM2A1333C9 2x2GB---------------46.99$
Antec 300------------------------------49.79$